The present disclosure relates to an analysis unit for performing a polymerase chain reaction, a method for operating such an analysis unit, and a method for producing such an analysis unit.
The digital polymerase chain reaction permits the detection of individual DNA sequences in a cavity array. For this purpose, n DNA molecules are randomly distributed together with a biochemical amplification system (polymerase chain reaction (PCR)) on m microcavities of a chip, where n is normally smaller than m. In each cavity, in which one DNA molecule was initially present, millions of identical copies of the DNA molecule are generated and, at the same time, a detectable signal is generated. By counting the signals, it is thus possible, after the polymerase chain reaction, to distinguish “digitally” between empty cavities (=0) and cavities with a DNA molecule (=1).
In commercially available systems for digital polymerase chain reactions, a biological sample is initially disrupted, and the DNA is then purified and extracted.
Microfluidic diagnostic systems such as lab-on-a-chip (LOC) systems permit the miniaturized and integrated performance of complex work steps such as fully automated sample preparation. In such lab-on-a-chip systems, the sample material to be tested can first of all be amplified by means of polymerase chain reaction and then analyzed on a microarray. The link between both operations and the multiple steps of the process result in a protracted processing time and complex processing. By contrast, the digital polymerase chain reaction makes it possible for DNA molecules to be specifically amplified and quantified in one step.